Territory



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(N0 Model.)

STEAM ENGINE.

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fPatente'd-Mar. 1l, 1898.

-mo Model.) 'I 4 .2 Shak-$119552.'- l

lM500-BB.. y STEAM ENGINE.

NQ.`599,830. Patented Mar. 1, 1898.

jjj" f n n gesf- A cording to my invention.

UNITED STATES PATENT OFFICE.

` I yALTON E. COBB, OF PHCENIX, ARIZONA TERRITORY.

STEAM-ENGINE.

SPECIFICATION forming part of Letters Patent No. 599,830, dated March 1, 1898.

'Application iiled May 16, 1894. Serial No. 511,433. (No model.)

To all whom it may concern.-

, Be it known that I, AL'roN E. COBB, a citizen of the United States, residing at Phoenix, in the county of Maricopa and Territory of Arizona, have invented certain new anduseful Improvements in Steam-Engines; and I do hereby declare the following to bea full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to steam-engines; and it consists in certain improvements in the valve-gear and operating mechanism, as hereinafter set forth and claimed, the object of the invention being to sov construct the exhaust and cut-off valves and operating mech,- anism that quick port opening and cut off may be obtained automatically.

v In the accompanying drawings, Figure 1 represents in side view the valve-operating mechanism of a steam-engine constructed ac- Fig. 2 illustrates in section the steam-chest and other details. Fig. 3 illustrates in section the exhaust and cut-od valves. Fig. 4 further illustrates the valves in section. Figs. 5 and 6 show different views of gearing through which the main slide is actuated. Fig. 7 is apartial side view of an operating-slide. Fig. 8 illustrates the bearings of two slides.

A designates the steam-chest, in which is located a slide-valve B, a cut-o valve C being mounted on valve B, as shown. In the steam-chest are mounted on. the same plane three rocking shafts, which have bearings in the walls of said steam-chest,the central shaft being indicated by D andthe other two shafts being indicated by E and E', respectively. The shaft D has an arm. d, "which extends downward therefrom and has a loose connection with the slide-Valve B, as seen at c, and the shafts E E have arms b and b', respectively, Which have loose connections d with the cut-olf valve C, so that the valves B and C may be severally actuated by the rocking of shaft D and shafts E E. Each of the said rocking shafts is extended at one end, a stuffing-box f being provided to form a close joint of the shaft and the wall of the steam-chest. The opposite ends of the shafts are provided with bearings g within the steam-chest., On the extended ends of the shafts E E are secured the arms F F', which extend downward and connect with other devices, as hereinafter set forth.

G indicates the crank-shaft of the engine, which is connected by beveled gear-wheels h with a driving-shaft H, which is mounted in bearings t', collars j being made fast to said shaft H. A standard I is adjacent to the driving-shaft H, and a pin Z-extends from said standard and forms the axle of a beveled gear-wheel la, which connects with a beveled gear-wheel m on the drivingeshaft H. A iixed pin n extends from wheel 7c near its periphery into a slot in an arm o, which extends down from a horizontal slide J, which is the main slide, and actuates the cut-off valve C before mentioned. The slot in arm ois adjustable, one side being formed by a bolted strap p, which may be moved for the purpose of taking up wear.

The slide .I moves on two bearings Q, which project laterally from the cylinder or the steam-chest. Each bearing piece q is between two lgs r, which are fast on the slide J. Washers or brasses s are placed one above and the other under the bearing-piece q and pressed by set-screws u, passed through the lugs r for the purpose of taking up lost motion. (See Fig. 8.)

K indicates a vertical governor-shaft which is mounted in bearings t and has connection with the driving-shaft H by beveled gearing L. Along sleeve Mis placed on the governorshaft, and collars t and a spring w, on which said sleeve rests, serve to hold shaft K in position. An arm oc extends from shaft K and has a weight y, which is adjustable on said arm and is intended to regulate the speed of the engine. Two of the collars o are fast on the sleeve M, and between them is a collar z', which'is loose on said sleeve and has pivotally connected with collar z two arms a',

-which extend in opposite directions and are each connected with a wedge-shaped slide b' hereinafter referred to. A collar o is secured to the upper end of the sleeve M, and to the upper end of shaft K is secured ahorizontal bar e', either end of which is slotted or bifurcated, as shown. Two rods or arms d are connected at their lower ends with the collar c' Von sleeve M and extend upward through the slots in the horizontal bar e' and are pivoted IOO at their upper ends to the inner ends of the governor-arms N, which latter are pivotally connected with the slotted bar c', as seen at f', so that the downward movement of the collar c throws outward the governor-arms N, and the upward movement of said collar brings the arms N inward.

The slide J has two hooks O pivotally connected with it, as seen at g', said hooks being pressed upward by springs h', connected with said slide and provided with adjustingscrews h2. Adjacent to each hook O is a wedge-shaped slide b', which has a bearing z", on which said slide may move forward and backward, said bearing being carried by a standard j'. The slides b being, as before stated, connected by arms a with the collar 5, which is loose on the sleeve M of the governor-shaft, said slides are moved forward and backward by the vertical movements of said sleeve.

On each of the hooks O is a projecting pin or stud Z in position to be impinged against by one of the wedge-shaped slides b', so as to press downward said hook, so that as the hook is moving forward with the slide J it may pass the catch-arm F or F', which is just above said hook, and the latter, having passed the catch-arm, is immediately raised by a spring h/ to connect with said arm and is held up until the slide J moves back and the cutoff is required. The stud Z' then strikes the slide b/ and the hook is again pressed down until the catching-arm is passed, and the cutoff is immediately closed by the action of the spring m, one of these springs in being connected with each of the catch-arms F F above the connection of the catch arm with the rock-shaft. Each spring ml is threaded at the end nearest the governor-shaft, a nut n being placed thereon, by means of which the spring may be tightened so as to act quickly, and a quick eut-off may be eected.

Each of the catch-arms F F is connected by a rod n2 with a pivoted elbow-lever 0', which is connected with the stem p of the plunger in an air dash-pot q', which is for the purpose of stopping the eut-o valve C when it is sprung shut or over a port of the slidevalve B.

P indicates a slide by the movement of which the slide-valve B is actuated, said slide having movement on two bearings r', which are similar in construction to the bearings of the slide J before described, being provided with washers and adjusting-screws passed through lugs. The slide P has formed at one end a rectangular frame Q, which has an inner upper shoulder s and a lower shoulder s2. A vertical shaft R is mounted in bearings t and provided with collars u', said shaft having connection at its lower end with the driving-shaft H through beveled gearing S. At its upper end the shaft R has a beveled gearwheel T, which engages with a beveled gearwheel U, which is mounted on an arm w', which extends from the cylinder or from the steam-chest, and a pin t" is fixed to the wheel U near its periphery, said pin being in position for contact with each of the shoulders SMS2 successively as the wheel U is rotated, motion being thus imparted from the driving-shaft H to the slide P. The pin o first moving against the shoulder s moves the slide in one direction a certain distance, when the pin leaves that shoulder and the slide stands still until the pin comes in contact with the lower shoulder 32, when the slide moves in the opposite direction.

Fixed to the extended end of the central rock-shaft D is an arm 7j', the free end of which is slotted or bifurcated, so that a loose connection is formed of said arm y with the slide P by a pin or stud on the slide, and as the latter is moved forward and backward the slide-valve B is actuated.

In Fig. 4 is shown the relative position of valves when the ports are about to open to admit steam into the cylinder V, the valve B having port-openings 3 and t moving in the direction indicated by the arrow 5 and the cut-ofi' valve C moving on valve B in the direction indicated by the arrow 6. In Fig. 3 are shown ports wide open and valve C still moving from the port as it would under a heavy load or low steam. Thus a quick portopening and a quick cut off are obtained by the movements of the valves B and C in opposite directions, whereby the full steam-pressure from the boiler on the piston is obtained, from which a considerable increase in the amount of horse-power of the engine and a saving of fuel result. lVhen the port is wide open, the movement of the slide-valve B stops, leaving the port open until the cut-off closes, unless the cut-olf is late, in which case the cut-off is effected by the valve B, as it would be in a common slide-valve engine. Such stopping of the valve B is caused by the pin o on gear-wheel U passing from the shoulder s in the frame Q ofthe slide P, when the latter stops and does not move until said pin o' strikes the shoulder S2, when the slide P commences its reverse movement and effects a cut-0E, if the automatic cut-off is too late, as it would be in ease of low steam or when just starting, and also effects the exhaust.

I claiml. The combination, with a slide valve which moves on a steam-cylinder, of a rockshaft mounted in the steam-chest and provided with an arm which has a loose connection with said slide-valve, another arm, bifurcated and made fast to the extended end of said rock-shaft, a slide having, at one end, a loose connection with said bifureated arm, a rectangular frame on one end of said slide, said frame being provided with an upper and a lower shoulder, gearing adapted to connect with said shoulders and engage said slide, and driving mechanism, substantially as set forth and described.

2. The combination, with the cut-ofi. valve of an engine, of two rock-shafts having arms IOO IZO

loosely connected with said valve, catch-arms,

secured to the extremities of said rock-shafts,

a slide having a reciprocating movement, two hooks pivotally connected with said slide and adapted to connect with said catch-arms, springs adapted topress upward said hooks and other springs adapted to actuate said valve th rough said rock-shafts, wedge-shaped slides, adapted to engage said hooks, a vertical governor-shaft with weighted arms, a movable sleeve on said governor-shaft, connected by two pivoted arms, extending in opposite directions, with said wedge -shapcd slides, substantially as set forth and described.

3. The combination with the cut-olf valve of an engine and a main slide having connection therewith, of two wedge-shaped slides in position to connect with said main slide, a vertical, governor-shaft, a movable sleeve on said shaft, a spring supporting vsaid sleeve, two pivoted arms connected with said sleeve and with said wed ge-shaped slides, whereby reciprocating movement is imparted to said wedgeshaped slides, substantially as set forth and described.

4. The combination with two wedge-shaped slides, of a governor-shaft, a sleeve, loose on said shaft, a spring supporting said sleeve, a collar on the upper end of said sleeve, a horizontal, slotted bar, secured to the upper end of said shaft, two governor-arms extending through and pivoted to said slotted bar, two arms or rods connected with said collar and pivotally connected with the upper ends of said governor-arms, and two pivoted arms connected with a lower collar on said sleeve and with said wedge-shaped slides, substantiallyV as andv for the purposes described.

, In testimony whereof- I have afxed my signature in presence of two witnesses.

ALTON E. COBB.

Witnesses:

PHILIP K. HICKEY, SEVERIN P. HOEFER. 

